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RFC 633 UNKNOWN ARPANET · MAINTENANCE · OPERATIONS

IMP/TIP preventive maintenance schedule

A monthly preventive maintenance schedule for ARPANET IMP and TIP machines.

On rfc-editor.org ↗
PUBLISHED
March 1974
AUTHORS
A.M. McKenzie
STREAM
Legacy
OBSOLETED BY
RFC 638 — IMP/TIP preventive maintenance schedule
MAINTENANCE FREQUENCY
Monthly
RESERVED SOFTWARE MAINTENANCE WINDOW
Tuesday, 7 a.m. to 9 a.m. Eastern Time
EXAMPLE BBN IMP WINDOW
First Monday, 0830-1130 Eastern Time
DOI
10.17487/RFC0633
LINEAGE · FROM THE RFC INDEXOpen full graph →
'74RFC 633IMP/TIP preventive maintenance schedule'74RFC 638IMP/TIP preventive maintenance schedule

RFC text

Original text · RFC Editor View on rfc-editor.org ↗ 
Network Working Group                                        A. McKenzie
Request for Comments: 633                                        BBN-NET
NIC: 30240                                                March 18, 1974


                  IMP/TIP Preventive Maintenance Schedule

   This note presents the current IMP/TIP Preventive Maintenance
   schedule.  Preventive Maintenance is scheduled on a monthly basis and
   a given machine is normally scheduled at the same time each month;
   wherever possible the time is chosen to coincide with the PM time for
   the Host(s) at the site.

   It is sometimes necessary to reschedule PM's because of network
   connectivity considerations or for other reasons.  Whenever this is
   necessary we will follow the usual procedure for scheduling down time
   with our "primary contact" at the site.  Permanent changes to the
   schedule will he announced via the RFC mechanism.

   PM's normally do not require the IMP/TIP to be taken down.  However,
   machines must be taken down in some cases, so no one should rely on
   the machine remaining available through the PM period.

   PLEASE REMEMBER THAT TUESDAY MORNINGS FROM 7am TO 9am ARE RESERVED
   FOR NETWORK SOFTWARE MAINTENANCE.


   All times shown below are Eastern Time.

    First Monday (of each month)

        BBN IMP  [0830-1130]

        NCC TIP  [1130-1430]

        WRIGHT-PATTERSON  [1300-1700]

    First Tuesday

        BBN TIP  [0830-1130]

        UCSB  [1130-1430]

    First Wednesday

        CARNEGIE  [0830-1130]

        SRI [1130-1430]

    First Thursday

        SDAC  [0830-1130]

        UTAH  [1030-1330]

        NORSAR  [0830-1130]

        LONDON  [0830-1130]

    Second Monday

        MIT-MAC  [0830-1130]

        MIT-IPC  [1200-1500]

        DOCB  [1030-1330]

    Second Tuesday

        MITRE  [0830-1130]

        USC [1130-1430]

    Second Wednesday

        CCA  [0830-1130]

        STANFORD  [1130-1430]

        XEROX  [1500-1800]

        RADC [1430-1730]

    Second Thursday

        BELVOIR  [0830-1130]

        UCSD  [1130-1430]

        RML  [0930-1230]

    Second Friday

        TYMSHARE  [1300-1600]

    Third Monday

        HARVARD  [0830-1130]

        UCLA  [1000-1300]

        KIRTLAND  [1600-1900]

    Third Tuesday

        RAND  [1130-1430]

        SDC  [1530-1830]

    Third Wednesday

        ILLINOIS [0930-1230]

        ARPA  [1800-2100]

        AMES IMP  [1130-1430]

        AMES TIP  [0800-1130]

        HAWAII  [1130-1430]

        MOFFETT  [1500-1600]

    Third Thursday

        ETAC  [0830-1130]

        FNWC  [1130-1430]

    Fourth Monday

        CASE  [0830-1130]

    Fourth Tuesday

        NBS  [0830-1130]

        LBL  [1130-1430]

    Fourth Wednesday

        LINCOLN  [0830-1130]

        RUTGERS  [1000-1400]

    Fourth Thursday

        GWC  [0930-1230]

        ISI  [1300-1600]

        ABERDEEN  [0830-1130]

    Fourth Friday

        LLL  [1330-1730]











       [ This RFC was put into machine readable form for entry ]
       [ into the online RFC archives by Alex McKenzie with    ]
       [ support from GTE, formerly BBN Corp.           2/2000 ]

ISO Plain Language

On this page
PROBLEMNetwork users needed to know when IMP and TIP machines were scheduled for preventive maintenance and might be unavailable.
MECHANISMThe RFC lists monthly maintenance windows by week, day, site, and Eastern Time, and describes how schedule changes would be handled.
HISTORICAL CONTEXTRFC 633 is an informational maintenance schedule and was obsoleted by RFC 638.

§1How the Maintenance Schedule Works

Preventive maintenance is scheduled monthly, and a machine is normally scheduled at the same time each month. Where possible, the schedule coincides with preventive maintenance for the host or hosts at that site.

Maintenance normally does not require taking an IMP or TIP down, but the RFC warns that machines must be taken down in some cases. Users should not rely on a machine remaining available during its maintenance period.

Each machine usually has the same maintenance time every month. It may stay online, but the RFC warns users not to count on that.

§2Maintenance Windows

The schedule is arranged by week of the month and weekday, with each site followed by a time window. All listed times are Eastern Time. For example, the RFC lists BBN IMP maintenance on the first Monday from 0830 to 1130 and UCLA maintenance on the third Monday from 1000 to 1300.

Tuesday mornings from 7 a.m. to 9 a.m. are reserved for network software maintenance.

The table gives each site's maintenance day and time in Eastern Time. Tuesday mornings from 7 to 9 are reserved for network software maintenance.

§3Rescheduling Maintenance

Network connectivity or other reasons may require a preventive maintenance change. BBN says it will use the usual procedure to schedule downtime with the site's primary contact. Permanent schedule changes will be announced through the RFC process.

If maintenance needs to move, BBN will coordinate downtime with the site's primary contact. Permanent changes will be announced in an RFC.